This invention relates to apparatus and assemblies for storing, transferring, and transporting automobile windshield and window covering panes of glass.
Base frames for truck mounted glass rack carriages of the type disclosed in U.S. Pat. No. 6,247,601 issued Jun. 19, 2001 to Norton, et al., typically comprise a latch bar or lock bar spanning between forward and rearward ends of the base frame, such bar extending substantially parallel to roller tracks formed by the lateral left and right sides of the base frame. Such base frame mounted lock bar typically has a series of longitudinally spaced slots for selectively engaging with an alternately extendable and retractable latch or bolt. Such latch or bolt is typically supported upon a second glass carrying frame which is rollably mounted upon the tracks of the base frame. In operation of such assembly, withdrawal of the bolt or latch frees the glass carrying frame for rolling movement; and extension of the bolt or latch into one of the lock bar""s slots resists rolling movement of the glass carrying frame.
A defect or disadvantage of assemblies such as described above is that operation of the glass rack upon an incline undesirably allows gravity to move and accelerate the glass carrying rack when the bolt is retracted and disengaged. Upon such disengagement an operator may be undesirably required to manually push or pull the weight of the glass rack up the incline.
The instant inventive assembly overcomes or ameliorates the problems described above by configuring the lock bar cylindrically, by configuring the bolt receiving slot to extend continuously along and helically about the lock bar, and by providing rotating means allowing the bolt and such slot to rotate with respect to each other. Such inventive configurations of the lock bar and bolt allow the lock bar and bolt assembly to perform triple functions of locking the glass carrying rack in place, extending such rack for loading and off-loading of glass panes, and retracting such rack for storage and transportation of glass panes.
The instant inventive glass pane handling assembly preferably comprises a first rectangular base frame having left and right sides or rails which are preferably configured to include left and right roller track surfaces. Preferably, the left and right rails of the base frame comprise inwardly opening xe2x80x9cCxe2x80x9d channels, the concavities of such channels being fitted for receiving rollers. The left and right rails may suitably be differently configured provided that the rails present laterally paired longitudinally extending surfaces which are suitable for rolling support of rollers, wheels, linear roller bearings, linear ball bearings, or which are suitable for sliding support of skids. Cross beams preferably span between and rigidly interconnect the side rails, the cross beams in combination with the side rails forming a rigid bar frame. Typically, such frame is fixedly bolted to a truck bed.
A second frame or carriage for glass rack support is preferably similarly configured as a rigid bar frame, such frame preferably being fitted for receipt and longitudinal movement within the base frame. Rollers are preferably rotatably mounted upon the left and right sides of the glass rack supporting frame, such rollers extending laterally outward into the concavities of the preferred xe2x80x9cCxe2x80x9d channels of the left and right side rails of the base frame, such rollers allowing the glass rack supporting frame to roll longitudinally within the base frame. Suitably, linear roller bearings, or linear ball bearings may be alternately interposed between the glass rack supporting frame. Suitably, though less desirably, skids or slides comprising a high density low friction plastic such as high density polyethylene (HDPE) may be alternately interposed for facilitating sliding longitudinal movement.
A lock bar is necessarily mounted upon the base frame, preferably spanning between such frame""s cross bracing members, and preferably extending substantially parallel to such frame""s side rails. The lock bar necessarily has a bolt receiving slot extending helically along its longitudinal axis. The glass rack frame is necessarily interconnected with the lock bar by means of a bolt or tooth having a distal end, the bolt being mounted upon the glass rack frame and positioned for extension of its distal end into the lock bar""s helical bolt receiving slot. Preferably, the bolt is configured helically, the bolt""s helix angle and radius of curvature matching those of the bolt receiving slot of the lock bar.
The lock bar is preferably rotatably mounted at forward and rearward ends upon the base frame, such mounts allowing the lock bar to rotate about its longitudinal axis. Where the lock bar is mounted rotatably, the preferred helically configured bolt is preferably rigidly mounted upon the glass rack supporting frame. Where the inventive assembly utilizes such preferred configuration, alternate rotation and counter-rotation of the lock bar alternately drives and pulls the helical bolt, alternately extending and retracting the glass rack supporting frame. The matching helix angle of the bolt receiving slot and the bolt is preferably small, between eight degrees and twelve degrees, allowing the bolt and slot to function in combination as a lock in absence of application of rotational torque to the lock bar.
Suitably, the lock bar may be alternately rigidly mounted upon the base frame, and the preferred helical bolt may accordingly be rotatably mounted upon the glass rack supporting frame, such configuration allowing rotation and counter-rotation of the helical bolt to similarly alternately extend, retract, and fix in place the glass rack supporting frame. Such alternate configuration is less desirable since it requires mounting of motor means upon the moveable glass rack frame.
Preferably, the rotatable lock bar or, as the case may be, the rotatable helical bolt, are rotatably mounted by means of ball bearings. Suitably, bearing sleeves or roller bearings may be alternately utilized.
Where the instant inventive assembly is configured to include the preferred rotatably mounted lock bar, rotating means comprising a torque applying mechanism, preferably a reversible electric motor, but suitably an hydraulic motor or pneumatic motor, is utilized for rotating the lock bar. Power is preferably transmitted from the torque applying mechanism (electric, pneumatic or hydraulic, as the case may be) via a belt and pulley assembly, and preferably such mechanism is controlled by a network of power transmitting lines which incorporate a three position switch or valve, the three way switch or valve having a locked xe2x80x9cpower offxe2x80x9d position, a forward motion position and a rearward motion position. Where a rotatable helical bolt and fixed lock bar assembly is alternately provided, such motor and belt and pulley assembly is preferably operatively connected to a rotatable nut which annularly supports the helical bolt, such nut being rotatably mounted upon the glass rack carrying frame.
Means for supporting glass panes upon the glass rack carrying frame are necessarily provided, such means preferably comprising a plurality of removably attached upwardly extending arms.
In operation of the inventive assembly, manipulation of the three way switch or valve alternately and selectively rotates, counter-rotates, and stops the torque applying mechanism, resulting in selective actuation, counter-actuation, and stopping of rotating motion of the lock bar with respect to the bolt, such selective actuation selectively extending, retracting, and locking in place the glass rack carrying frame with respect to the base frame.
Accordingly, it is an object of the present invention to provide a glass pane handling assembly which includes a base frame, a glass rack carrying frame adapted for longitudinal rolling or sliding movement with respect to the base frame, and comprising a lock bar and bolt assembly adapted for rotation with respect to each other, such assembly comprising nesting bolt and helical slot structures capable of alternate extension, retraction, and locking of the glass rack carrying frame.
Other and further objects, benefits, and advantages of the present invention will become known to those skilled in the art upon review of the Detailed Description which follows, and upon review of the appended drawings.